Process for treating copper.



APPLICATION FILED FEB. 16. 1911.

Patented N 0v. 14, 1916.

,WITIVESSES W61.

4 OH/VEY FRANK L. ANTISELL, OP PERTH AMBOY, -NEW JERSEY.

PROCESS FOR TREATING COPPER.

To all whom it may concern:

Be it known that 1, FRANK LINDEN ANTI- I SELL, a citizen of the United States, and a resident of Perth Amboy, county of Middlesex State of New Jersey, have invented certain new anduseful Improvements in Processes for Treating Copper, of which the following is a specification.

My invention relates to a new and improved process for treating copper.

The objects of the invention will appear from the hereinafter description.

Before describing my improvements it. may be well to briefly outline the prevailing process and accepted principles relating to the refining of what is known as cathode copper which results from the electrolytic refining of copper.

Copper in cathode form will run in conductivity (Matthissen standard) as high as 102 per cent, and the copper contents of said cathode will .be as high as 99.97 per I cent.

By the present process of melting the cathode copper into proper shape for drawing into wire or rolling into cakes both the electric conductivity and copper contents are lowered by reason of the melting down being performed in an ordinary reverberatory furnace which is generally heated by coal, and the flame being only under partial control at times, the character of the flame constituting changes from an oxidizing flameto a reducing flame. While each kind of flame is valuable at the proper time in the melting down, at other times such a flame is detrimental. The tendency of the oxidizing flame is to form copper oxid'as well as oxids of the other impuritiesthat may be present in. the molten copper, such as iron, zinc, etc., which are skimmed off with the oxid slag. The sulfur which has been dissolved during the process of melting passes off as sulfur dioxid and part of the arsenic and antimony passes off as lower oxids. This oxidizing is generally facilitated by flapping or blowing air in the molten copper. After this the molten copper is subjected to the step in the art 0 what is known as poling where charcoal is spread 'over the surface of the molten copper and a stick of green wood is forced under the surface of the copper which reduces the oxids of copper and to some extent the oxid impurities in the molten copper. This step is carried on until the oxids of copper are reduced to some or 1;

Specification of Letters Patent. 7

Patented Nov. 14, 1916.

Application filed February 16, 1911. Serial No. 608,935.

of 1 per cent, which copper oxid is permit ted to remain in the bath of copper when refined by the usual methods, as pointed out farther on. If the step of poling is carried to completely reduce the higher oxids, that --is, the oXids of arsenic and antimony which are present, they are reduced to a metallic state and alloy with the copper, reducing its conductivity. In addition to reducin said oxids the copper absorbs the gases fro f the green Wood and ,overpoles or spues are produced Which'give the copper a high pitch which makes it brittle and lower in conductivity. In this condition reflapping and repoling of the molten copper 1s necessary. It is therefore evident that it isfdesirable to reduce the oxids of copper to the lowest per cent. and still not affect the other oxids present, such as arsenic and antimony.

Attempts have been made by others to melt copper withoutcontaminating it by the flame,which contamination is proportionate to the time the flame plays on the copper. One of the various attempts to obtain this result has been to melt the cathode copper under cover or blanket of suitable character in the nature of non-metallic salt of which boronxtrioxid is one, which will prevent the air' and gases coming into contact with the copper as it melts. This attempt has been found to be unsatisfactory in practice, however, owing to the increased amount of heat necessary to melt the cop-per under the blanket. Furthermore, the intense heat necessary to melt the copper under the blanket causes the blanket to flux the silica copper from said furnace in its molten conditionunder a blanket which covers the surface of the copper and prevents its contact with air, gas'or other contaminating elements. -While I prefer to preheat'the copper, yet it is not necessary.

My process maybe carried out by different apparatus, but in the accompanying drawing I have shown two types of. apparatus especially adapted for my purpose.

Referring to the drawing, Figure 1 is a section of a melting furnace and a purifying furnace showing the relative arrangement and the connection between the same. Fig. 2 is a sectional view of the preferred form of treating furnace. Fig. 3 is a section on line 3 of Fig.2.

In the drawing the part marked A represents the melting furnace. 10 isthe crucible thereof.

11 is the superstructure for preheating the charge.

12 represents the oil burners communicating with the furnace to feed the oil fuel thereto.

13 is a tap hole at the bottom of the furnace leading to the spout 14.

B is a reheating or'treating furnace which has a closed chamber 15 having an opening 16 in the top thereof in communication with the spout 14. This chamber has a taphole 17 communicating with the spout 18. The chamber 15 is provided with a cover or blanket C of non-metallic salt, preferably boron trioxid. Under the chamber 15 is a combustion chamber 19 heated by liquid fuel passing through the burner 20.

In operation, the charge W asfed into the furnace A is heated and reduced to a through the opening 16 and into the chamber 15 through the blanket C, This molten copper is drawn from under the blanket C in chamber 15 through the tap hole 17 into thespout 18 where. it is conveyed to proper molds not shown. The molten metal in the chamber 15 is kept in its proper heated condition by the burning of the fuel in the combustion chamber 19.

' Referring to the construction shown by the two compartments.-

Figs. 2 and 3, D is a furnace divided into two compartments 21 and 22 by the partition 23, leaving a passageway 24 between The furnace is heated by a supply of liquid fuel through the burner 25. 26 is a stack communicating with the chamber 22. The bottom\of the stack is inclined as. shown at 2:7, down which the charge W is passed through 'an opening 28. C is the blanket or cover of non-metallic salt, preferably, boron trioxid in the chamber 21. 29 is a tap hole closed by a plug of clay 30 in the usual manner. 31 is an opening in the chamber 21 above the blanket.

In operation, the furnace is heated by'the fuel fed to the burner 25, the products of combustion passing up through the stack 26.. The charge W is fed through the opening 28, down the incline 27 where it is preheated by the products of-combustion. The charge falls down into the chamber 22 As indicated in the drawing, the melting- I prefer to accomplish by means of an oil fuel furnace which I term a combination melting and purifying furnace, the melting part being in the nature of a reheating furnace, where the flame after being thoroughly consumed in the combustion chamber passes over a relatively small bath of copper, ascending through the stack or cupola of the furnace, meeting the incoming charge, cathode sheets, which are thereby heated to almost fusing temperature, the hearth or crucible (terms used in blast furnace practice) adding little more than the heat of fusion to the already hot copper This process has been carried on so rapidly and efliciently that the copper has not had time to absorb but a very small per cent. of the impurities thatwould have been absorbed had the metal been melted down in the ordinary furnace, where possibly 200,000 to 400,000 lbs. of copper are piled in the open hearth and melted down during a period of 5 or 6 hours to a fiat condition; that is to say, there is a small layer of molten copper over the mass of unmelted copper on the bottom ofthe furnace.

To melt the copper off the bottom, it is necessary to fire the furnace hard for severalhours by the very inefli'cient process, which during this period cannot betermed fusing in the strict meaning of the sense, as it is rather one of dissolving where the upper layer of copper is kept in a molten condition and the copper submerged is liquefied by the contact of the molten copper.

As shown in the drawing, burners 12 and the burner 25 are supplied with valves for the purpose of so regulating the burners as to produce an oxidizing flame.

As the laws of efliciency of heating surfaces are based fundamentally upon the difference in degrees of temperature between the absorbing medium and the heat emanating medium, and as molten copper has a temperature of in round numbers, 2000 F and assuming that the flame over the bath has a temperature of 2500 (a very usual observed temperature), there is only some 20 per cent. of the heat that is efiicient for melting the copper, the per cent. of the heat passing out of the stack at 2000.-. But by preheating the copper the gases pass from the-furnace at a-much lower temperature, resulting in both an economy of fuel amount of foreign substances absorbed by the copper, by reason. of the time interval reduced in minutes in place of hours for melting, and immediately after melting,

5 running into a separate compartment from the melting compartment where it may be refined by means of suitable fluxes, oxidizing or reducing agents, as the treatment may require.

By means of my process a certain reduction is effected by poling or otherwise sub jecting the copper to the action of reducing agents as the treatment may require, after which the molten copper is delivered to the third compartment through the port 24,

- where the copper comes in contact with the boron-trioxid which absorbs more or less of the unreduced oxid without any possi bility of reducing the arsenic and antimony.

The flux boron-trioxid is'used only forthe purpose of super-refining copper which would be refined by the standard process up to this point. It is therefore evident that by charging copper in the preheating chamber I am able to melt continuously,

' transferring the same to the purifying chamber and casting either continuously or intermittently as I desire.

I prefer to build my furnace partltioned as shown by Figs.'2 and 3 of the drawing and leave a large communicating port between the partition and bottom of the furnace, and depend upon the thermal conductivity of the copper for keeping the metal in the purifying compartment at a suitable temperature for refining. This construction would also offer some advantage due to the osmotic pressure which would be exerted between refined and unrefined cop- 40 per tending to keep it in a nearly uniform condition throughout the melting compartment.

In carrying outmy process, the preheating is effected by means of a heat which is not sufficient to melt the copper, and

therefore the step. of pre-heating in my process is clearly distinguishable from the initial action of the melting heat upon the copper. The pre-heating is never accomplished by the action of the melting heat, but is always accomplished by a heat which is always less than the melting heat and jecting the molten copper to the action of.

a purifying agent and then conducting it under a blanket. 2. The process of refining copper, which ,melting zone, melting the preheated copper consists in melting the copper and then sub- 'jecting the molten copper to the purifying action of a blanket or cover of a nonmetallic salt.

3. The process of refining copper, which consists in melting the copper and conducting the moltencopper under a blanket or cover of boron trioxid.

4. The process of refining copper, which consists in preheating the copper, heating the preheated copper until it becomes. molten, and then conducting the molten copper under a blanket containing a purifying agent to cover the surface of the molten copper.

5. The process of refining copper, which consists in preheating the copper, heating the preheated copper until it becomes molten, and conducting the molten copper under a blanket of a non-metallic salt to pus5 rify said copper. r i

6. The process of refining copper, which consists in preheating the copper, heating the preheated copper until it becomes molten, and conducting the molten copper under a purifying blanket.

7. The 'process of refining copper, which consists in preheating the copper, melting the preheated copper in a furnace, conducting or conveying the molten copper to a chamber containing a purifying element or material.

8. The process of melt-ing copper by preheating to a high temperature outside of the as rapidly as possible, and transferring it to a refining chamber.

9. The process of melting copper by preheating to a high temperature outsideof the melting zone, melting the preheated copper as rapidly as possible, and transferring it to a refining chamber containing a purifying element or agent.

10. The process of melting copper by preheating to a high temperature outside of the melting zone, melting the preheated copper as rapidly as possible, and transferring it to a refining chamber under a blanket of a non-metallic salt.

11. The process of treating copper which consists in preheating the copper, heating the preheated copper until it becomes mol ten, and purifying the molten copper.

12. The process of treating copper which consists in preheating the copper, heating the preheated copper until it becomes molten, and refining the moltencopper by means of suitable purifying fluxes.

13. The process of treating copper which consists in melting the copper in a melting compartment, running the molten copperinto a separate compartment, and refining the copper in the latter compartment by suitable purifying fluxes.

14. The process of treating copper which 130 consists in preheating the copper, heating the preheated copper in a chamber until it becomes molten, transferring the molten copper into a compartment separate from the melting compartment, and refining the copper in the latter compartment by means of suitable purifying fluxes.

The process of treating copper which consists in charging the copper .into a chamber, continuously preheating and melting down the preheated copper, transferring the I same to a purifying chamber, purifying the copper in said chamber, and casting the copper from said purifying chamber.

16. The process of treating copper which consists in preheating the copper, melting the preheated copper continuously, transferring the molten copper to a purifying chamber, purifying the copper in said'chamher, and casting from said chamber.

17. The process of treating copper which consists in preheating the copper, melting the preheated copper continuously, transferring the molten copper to a purifying chamber, and purifying the copper in said chamber by suitable purifying fluxes.

18. The process which consists in preheating the copper, melting the preheated copper in a compartment by means of a flame, transferring the molten copper to an other compartment, and purifying thecopper in the latter compartment.

19. The process of treating copper which consists in charging the copper into a heating chamber, continuously preheating the copper and treating the preheated copper in the heating chamber by a flame until it becomes molten, and subjecting the incoming charge of copper to the outgoing flame. 20. The process of treating copper which consists in charging the copper into a heat,-

ing chamber, continuously preheating the copper in the heating chamber and treating the preheated'copper until it becomes molten, subjecting the incoming charge of copper to the outgoing flame, conducting the molten copper to aseparate chamber or com partment, and purifying the copper-in said separate compartment.

.21. The process of treating copper which consists in preheating the copper, melting 24. The process of treating copper which dizing flame, and continuously removing the copper.

26. The process of treating copper, which consists in heating copper in a chamber by means of the highly heated products of com bustion of a fluid burner producing an oxi dizing atmosphere, and removing the cop,

27 The process of treating copper, which consists in melting copper in a chamber by means of highly heated products of combustion, removing the copper, and subjecting the copper to a purifying medium.

28. The process of treating copper, which consists in melting copper in a chamber by means of the highly heated products of combustion of a fluid fuel burner, removing the copper to a point exterior of said chamber, and delivering the copper to a refining medium.

29. The process of treating copper, which consists in melting copper in a chamber by means of the highly heated products of combustion of a fluid burnen producing an oxidizing atmosphere, removing the copper to: a point exterior of the chamber, and gelivering the copper into a refining cham- 30. The process of treating'copper, which consists in continuously melting copper in an oxidizing atmosphere, continuously re moving the copper from the ox'idizing'atmosphere, and subjecting the copper to the,

action of a purifying medium.

31. The process of treating copper which consists in continuously melting copper in an oxidizing atmosphere, continuously removing the. copper from the oxidizing atmosphere, and continuously purifying the copper.

32. The'process of treating copper, which consists in continuously, melting copper in a chamber, by means of highly heated products of combustion producing an oxidizing flame, and removing the copper.

33. The process of treating copper, which consists in continuously melting copper in a chamber by mea ns of highly heated products of combustion, continuously removing the copper to a point exterior of said chamber, and continuously delivering the copper into a refining medium.

34. The process of treating copper, which consistsjin continuously melting copper in a chamber by means of the highly heated mosses products of combustion of a fluid burner producing an oxidizing atmosphere, thereby producing an amount of copper oxid in said copper, and liberating the oxygen from said oxid by subjecting the copper to the action of a purifying agent.

35. The process of refining copper which consists in melting the copper and then conducting the molten copper under a blanket containing a purifying agent.

36. The process of treating copper which consists in continuously melting the copper in an oxidizing atmosphere, removing the same from said atmosphere, purifying the said copper while applying heat thereto to maintain it in a molten state, and continuously discharging the molten copper.

37. The process of treating copper which consists in continuously melting the copper in a chamber by means of highly heated products of combustion, continuously removing the copper at a point exterior of said chamber, continuously delivering the consists in preheating, and thereby oxidizing the copper in a chamber by means of highly heated products of combustion of a hydrocarbon burner, and removing the copproducts of combustion of a fluid fuel burner, and removing the copper to a refining chamber at a point exterior of the first mentioned chamber.

ll. The process of treating copper which consists in continuously melting and oxidizing copper, and continuously removing the copper.

42. The process of treating copper which consists in continuously melting copper in a chamber by means of highly heated products of combustion, continuously removing the copper to a point exterior of said chamber, and continuously delivering the copper into a refining medium.

In Witness whereof I have hereunto set my hand, at the city, county, and State of New York, this fifteenth day of February,

FRANK L. ANTISELL.

In presence of ISABEL R. RICHARDS, FRANK EUFEMIA. 

